Image:1r9fTRUEBIOLUNIT.pdb

biological unit of 1r9f from http://www.rcsb.org/pdb/files/1R9F.pdb1.gz (REMOVED THE MODEL NUMBERS AND SECOND RNA)

From the PDB "Data files contained in the PDB archive (ftp://ftp.wwpdb.org) are free of all copyright restrictions and made fully and freely available for both non-commercial and commercial use. "